Springing for railway trucks



y F. w. HANKINS 2,242,212

SPRINGING FOR RAILWAY TRUCKS Filed Jilly 26, 19 0 WITNESSES: I N V EN TOR:

. Frederick Wifiznkins v Patented May 20, 1941 SPRINGING FOR RAILWAY TRUCKS Frederick W. Hankins, Philadelphia, Pa., assignor to The Pennsylvania Railroad Company, Philadelphia, Pa., a corporation of Pennsylvania Application July 26, 1940, Serial No. 347,597

2 Claims.

This invention relates to railway trucks and the "like, and especially to springing suitable for bolster type trucks. An important aim of the invention is to provide a wide range of'elasticity without necessity for making trucks larger than usual. The invention permits of a soft, yielding spring action for light loads, combined with a stifier action for heavy loads. In suitable forms of embodiment, the invention allows of easy adjustment or replacement to take care of wear, and relatively low maintenance cost. The action of the springing can be made comparatively very quiet, and the transmission of vibration and shock to the lading minimized. The invention is especially adaptable and advantageous for freight-cars, and can be directly substituted for the usual helical spring assemblies of such cars with great improvement in their riding qualities: in particular, objectionable going dead" by closing together of coils under severe shocks, which is generally characteristic of helical springs, can be altogether avoided.

Other features and advantages of the invention will appear from the following description of a species .or form of embodiment, and from the drawing. All :the features and combinations illustrated or described are of my invention, so far as novel.

In the drawing, Fig. l is a fragmentary side view of the mid-portion of a bolster type railway freight truck, with the left-hand portion in vertical section as indicated by the line and arrows 1-1 in Fig. 3; Fig. 2 shows a vertical section through the truck side-frame, bolster, and associated parts, taken as indicated by the line and arrows 11-11 in Figs. 1 and 3; and Fig. 3 is afragmentary plan view of the side frame, partly in horizontal section as indicated by the line and arrows 111-111 in Fig. 1.

The drawing shows only side of the truck, since the other side may be just like that illustrated. Accordingly, there is shown in Figs. 1 and 2 a side frame In, resembling those of present standard freight car trucks in general design and construction, with one end of a transverse bolster II that carries the load of the car body, as usual. Besides the usual axle-box jaws or housings (not shown), the side frame lo has the window opening i4 into which the bolster ll extends. This is well illustrated in Fig. 2, which also shows one of the truck wheels IS. The bolster end Ii may be guided for up and down movement relative to the frame III in any suitable manner, as by engagement of stop flanges l6. IS on the bolster with the usual guideways I1, I! at opposite sides of the window opening. Above and below the window I 4 are the usual top and bottom side frame members l8, 19. A support for the spring cushion means to be presently described may be provided in any suitable manner, as by widening the bottom side frame member I9, beneath the window 14, Fig. 2. In the present instance, the truck has a spring plank channel 20 interconnecting its side frames,

support H has socket recesses in which are engaged the corresponding dowel projections2l on the spring plank 20.

The cushion spring 22 here shown comprises a mass or block of highly elastic material, preferably suitably vulcanized live rubber, interposed between the frame support I!) and the bolster end H. The lower and upper portions of the rubber cushion are engaged in corresponding frames or housings 23, 24 associated with the support I9 and with the bolster Ii, respectively, and here shown as stout sheet metal pans of generally rectangular outline. These housings 23, 24 may be held in position by any suitable means of engagement, such as conical dowel projections' 25 on the housings which engage in corresponding socket openings in the spring plank 20 and in the lower side of the bolster |l,- or, as

shown in Fig. l, in a spacer or liner plate 26 interposed between the housing 24 and the bolster, and itself preferably secured to the bolster. As shown in Figs. 1 and 2, the housing 23 also has a central hollow boss 21 welded to its bottom at its central opening 28, and engaged in a socket hole 29 in the spring plank, which coincides with a like hole 30 in the frame member Is.

As shown in Figs.l and 2, the walls of the sheet metal housings 23, 24 have a slight outward flare, which facilitates die-pressing the housings to shape, as well as the installation of the rubber cushion 22 in them. They also have outturned or beaded lips 3|, which stiffen them mediate portion has its sides reduced or grooved all around, as in a concave such as shown at 32, to allow outward lateral expansion of the rubber within the housings under compression. Also, the upper and lower portions of the cushion 22 are (one or both) internally hollowed or cored to allow inward lateral expansion of the rubber within the housings 23, 24, where compressed: e. g., the cushion 22 may have a number of regularly distributed conical cavities or holes 33 in each end. As shown in Figs. 1 and 3, internal lateral expansion of the rubber under compression is additionally allowed for by making the cushion 22 in a plurality of rectangular sections or units 35 (extending transversely of the truck, or lengthwise of the bolster ll), each with concave groove recesses 32 on its side(s) adjacent the others, as well as on its outward exposed sides. In Figs. 1 and 3, there are three of the cushion sections or units 35, each with a longitudinal series or row'of three evenly space holes 33 in its lower and upper ends.

Suitable air passage may be provided for the escape and return of air from and to the cavities 33 when the spring cushion 22 undergoes compression and reexpands, such as vent openings 36 through.the bottoms of the housings 23, 24, in registry with the cavities 33, and (preferably) corresponding openings 31 in the web of the spring plank and in the spacer 26. The roughdeflections (due to track conditions), the lateral expansion of the rubber may take up all the room for expansion provided by the grooving 3| and the holes 33. When this happens, the ratio of stress to deflection will become higher for further deflection; but the cushion will not go dead, but continue to yield and absorb excessive shocks. It is perfectly practicable to proportion the parts so that the housings 23, 24, cannot come together under even the greatest shocks ever met with, so that the cushion 22 cannot go dead like a. nest of helical springs. The cushion 22 and its sections '35 will not break in service, and can not only be installed in new trucks, or in substitution for an entire set of helical metal springs, but can even (when suitably designed and constructed) be substituted ness of the cast surfaces of the frame support l9 and of the bolster ll adjacent the parts 20 and 28 allows free passage of air from and to the openings 36 and 31, though air holes 38 may be drilled through these parts in registry with the holes 36, 31, if desired. The change of the air in the cavities 33 that is provided in the manner described is beneficial as a means of getting rid of the heat of internal friction in the rubber 22, so as to'keep it from overheating injuriously.

Irrespective of the advantages above mentioned, the sectional construction of the cushion 22 facilitates manufacture and allows of better curing of the rubber, so that the elastic properties of the cushion can be made much superior to those usually realized in a like cushion made in one piece. Preferably, each section is made of one integral piece of extruded material, compounded of very pure rubber. The holes 33 also facilitate the curing of the rubber. The sections 35 can be individually tested under pressures greatly exceeding in intensity the maximum to whichthey are ever liable in actual service.

In service, the absence of enclosure about its midportion and its external reduction at 32 combine with the internal hollowing of its enclosed lower and upper portions at 33 to give substantially uniform elastic compressive deflection of the cushion 22 under increasing loads or stresses, and this range of uniform deflection may considerably exceed that due to maximum loading of the car. Under greater compressive piecemeal for one or more transverse rows of helical springs when one of the helical springs in a row breaks. The cushion 22 requires no more room than the equivalent metal springs, and gives greatly superior riding. By changing the thickness of the spacer or liner plate 26, the unloaded position of the bolster ll relative to the truck frame can be adjusted to compensate for wear of the truck wheels I5, or of the axle bearings, etc., not shown.

Having thus described my invention, I claim:

1. Springing for a railway car comprising, in combination, lower and upper hollow housings facing toward one another, and a series of live rubber cushion sections fitted side-to-side into said housings and thus substantially fixed in position in the housings, and holding thelatter apart, said cushion sections being separated along lateral zones at their mid-height by lateral reduction or recessing between their juxtaposed faces, and also having their upper and lower portions within the housings internally hollowed and empty, whereby lateral expansion is afforded the rubber inside the cushion substantially throughout the cushion height, partly between the cushion sections and partly within each section.

2. springing for a railway car comprising, in combination, substantially rectangular lower and upper hollow housings facing toward one another, and a series of substantially rectangular live rubber cushion bars fitted side-to-side into said housings and thus substantially fixed in position in the housings, and holding the latter apart, said cushion bars being separated along lateral zones at their mid-height by lateral reduction or recessing between their juxtaposed i faces, and also having longitudinal series of empty cavities in their upper and lower portions within the housings, whereby lateral expansion is afforded the rubber inside the cushion substantially throughout the cushion height, partly between the cushion bars and partly within each bar.

FREDERICK W. HANKINS. 

